Firefox Takes a Bite Out of the Canvas "Super Cookie"
 

Firefox 58 is going to become the first of the major browsers to do something about canvas fingerprinting, a devious, cookie-less way of tracking you on the web. Canvas fingerprinting relies on websites being able to extract data from HTML canvas elements silently, but in the future, users will be asked to give their permission before that extraction can take place, just as users of the Tor Browser are. Browser fingerprinting has risen to prominence in recent years as the go-to approach for companies who want to track you without giving you a say in the matter. It works by tracking your browser itself, rather than by tracking a beacon that's placed on your browser, such as a cookie, Flash LSO (local shared object) or DOM storage value. Fingerprints use information that's gathered passively from your browser such as the version number, operating system, screen resolution, language, list of browser plugins, and the list of fonts you have installed.

http://www.hardocp.com/news/2017/10/..._super_cookie/